Determination of the Fine Structure of a Halide Perovskite using High-resolution THz Spectroscopy and Solid-state Density Functional Theory

It has been believed that the short-range correlations of the methylammonium (MA) cations impact the high photovoltaic efficiency of the hybrid organic/inorganic halide perovskite. Employing high-resolution THz spectroscopy technique and solid-state density functional theory method, we have revealed new evidence on 16 correlation patterns of MAs in the MAPbBr3 crystalline system. By integrating the current structural information provided by other analysis methods, we have suggested a fine-structure model for the halide perovskites.